SOLUTION: A number of students go to a game costing a tital of $80. Eight studnets are ill and cant go. Each of the remaining kids have to pay $ 0.50 each. how many studenst went on teh bu

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Question 316621: A number of students go to a game costing a tital of $80. Eight studnets are ill and cant go. Each of the remaining kids have to pay $ 0.50 each. how many studenst went on teh bus?.

thanksyou so much!

Answer by ankor@dixie-net.com(22740) About Me  (Show Source):
You can put this solution on YOUR website!
A number of students go to a game costing a total of $80.
Eight students are ill and can't go.
Each of the remaining kids have to pay $ 0.50 each.
how many students went on the bus?.
:
Let s = the number of students that actually go
then
(s+8) = number that were scheduled to go
:
Actual cost (per student) - anticipated cost = .50
80%2Fs - 80%2F%28s%2B8%29 = .50
multiply equation by s(s+8), results
80(s+8) - 80s = .50s(s+8)
:
80s + 640 - 80s = .5s^2 + 4s
Arrange as a quadratic equation on the right
0 = .5s^2 + 4s - 640
Get rid of the decimal, multiply by 2
s^2 + 8s - 1280 = 0
This will factor because we know it has to be an integer solution
(s+40)(s-32) = 0
the positive solution
s = 32 students actually went on the bus
:
:
Check this by finding the cost of each scenario
80/32 = 2.50; actual price
80/40 = 2.00; we can see each had come up with 50 cents